Electro-Mechanical Resonant Oscillator
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- เผยแพร่เมื่อ 29 ต.ค. 2022
- In this video I'll show how to build a resonant mechanical oscillator that's driven by an electromagnet. The electromagnet is pulsed by a circuit
with an adjustable frequency, so it can be fine tuned to run at the exact resonant frequency of the spring-mass system. In this case that
frequency is about 11 Hz. The driver basically just consists of a 555 timer and a MOSFET to turn the coil on and off. In the future, i think i
need to use a feedback controller to do this, because even when i get the system to resonate, it eventually drifts out of phase and resonance
dies off (even though the frequency is matched).
This type of device is commonly found in the compressor section of compact cryocoolers for infrared imaging and other sensors that require
extremely cold temperatures to operate. Suspending the compressor pistons on a flat spring or "flex bearing" and driving them at resonance allows
for high power and efficiency even with the relatively weak forces between the magnets and the coils. This is analogous to a flywheel on a
crankshaft, but is lighter, smaller, and more reliable. By avoiding the need for the bearings and linkages present in a rotary system, this kind
of devbice can achieve an extremely long service life (some are rated for over 200,000 hours of operation) inside a hermetically sealed unit.
This is part of my investigation into building my own refrigeration system (and eventually cryocooler) without HFC's/phase change refrigerants.
Several months ago i made a video showing how i built a compressed air turbine which I intended to use as a Brayton cycle cooler, and while it
did work, the extremely loud noise made it impractical in a home environment, so I'm now investigating reciprocating systems like Stirling/Pulse
Tube/Thermoacoustic/Gifford-McMahon-type devices for generating extremely low temperatures.
Music Used:
Kevin MacLeod - George Street Shuffle
Kevin MacLeod - Groove Groove (Yes, this is the same song that's in Kerbal Space Program)
STL Files:
www.thingiverse.com/thing:559...
Metal Spring DXF file:
drive.google.com/file/d/1OX4C...
Driver circuit schematic:
drive.google.com/file/d/1chrH...
Further reading on cryocoolers:
www2.jpl.nasa.gov/adv_tech/co...
www2.jpl.nasa.gov/adv_tech/co...
Fabrication shop i used for the metal springs:
sendcutsend.com/
![Tesla Earthquake Machine [3D Printed]](http://i.ytimg.com/vi/l5rEW9QgJDc/mqdefault.jpg)
Hey guys, thanks for the comments. When I develop this into a linear compressor, I'll definitely be adding feedback to keep the resonance on frequency/in phase. I'll be using either a hall sensor for magnet position, or detect zero-crossing events on sense coils.
why dont you put sound through it see if you get some as its basically how a speaker works.
@@jediknight2350 You would't hear it
given you're turning it into a linear compressor, aren't you effectively making the inverse of Tesla's electro-mechanical oscillator, given he used steam/air pressure to create electricity, and you'll be using electricity to create pressure? (patent US511916)
Plz use metric si units.... the eng moved away from potatos vs tomatoes plzzzzz . . Your videos r great.
@@andretokayuk8100 bģ
Your jokes have the perfect resonant frequency for a nine and a half minute video. I really enjoy seeing you build things like your own winding rather than buying one.
super simple concept yet incredibly entertaining. absolute gold. also insanely smart to use it as a pump like that, cryo stuff is amazing. thank you for the amazing video!
It’s pretty wild that sterling motors are still a valid tech these days. Sweet build man.
A stirling powerd supmarine defeated part of the American fleet in a war simulation
Absolutely brilliant. I'd hoped this would be a build that measures its own resonant oscillation - in other words, add more or less mass to the coil-spring platform, and have it PID (or even just P) tune itself to the new mass. Such a thing would be surely handy in its own way for damping 3D printer oscillation resonance. But, even though this was different than what I'd expected it to be initially, it's still tremendously wonderful work.
Side note - you've already SendCutSend'd the springs, so it's too late for that build, but on the next one, consider making your spring coil width taper off with a slight logarithmic reduction as you approach the center of the coil. This will evenly distribute the flexing across the full length of each spiral, rather than the rather visible issue of the center of the spring not flexing at all, and the outside of the spring overflexing.
I was also expecting some kind of feedback. You could use it to adjust the frequency as well as the amplitude. Tweak the frequency. If the amplitude goes down reverse direction. Tweak frequency until the amplitude is greater than desired, then reduce the power fed to the coil until it's lower than desired, then tweak the frequency again. Repeat until you overshoot the resonant frequency and the amplitude starts to reduce. Then you can sweep slightly back and forth over the resonant frequency to see whether it drifts.
The smiley dude is me on caffeine
I've recently been learning a bunch of concepts that are present in this video at school! Awesome project.
Very nice to make some standalone thing for testing a part of a bigger system, I really like this approach.
Thanks for the cryocooler links, I'm also interested in building a DIY version of one that is able to atleast liquify air.
Liquify air? Sounds like a really "cool" experiment!
I'm so glad that i found your channel. Keep going!
Han Solo's voice speaking about electromagnetic fields. I am subscribed.
If you want to make it better you could develop the electronic part of the project to self-find the resonance. It coud be easily done by adding one more coil to sense the field (magnet position feedback) and one LM311 or similar comparator. Feedback could be also done via some 3 terminal hall sensor. In mid 50's they made clocks simply by making blocking oscillator with single transistor and the core of the blocking transformer was made resonant in some way. Eather by coupling it to small tuning fork (and then dividing oscillator pulse via flip-flops) or coupling it to a pendulum with a magnet and dividing pendulum movement mechanically...
To complicated. Just add a magnetic reed switch to break the circuit then all you need is a little power sorce. Nothing else. Car radios worked with tubes dependably using simple viberator to pulse dc then feed pulsed dc to step up transormer for the 80 volts needed for tube plate bias. No transistors or ic's needed. Just a simple device. Tesla almost shook a building to pieces with a pneumatic mechanical vibrator that worked in a very similar way. Also kit kat clocks have been wagging their tails and looking shifty eyed using the same electrical mechanical resonant vibratory circuit for many many years. Meow. Also, if you have some huge stones to move ,a certain man who built the coral castle in Florida had an interesting version that he created to do manipulate very huge stones.
My dad has a wall clock that works like that, and it's always fascinated me.
What an ... exciting project ...
thank you, I'll be here every saturday fro 3 to 5 pm
You do some downright artful work! Hat's off to you Sir.🌞
Great project, you can turn this into a actual oscillator by creating a feedback driven circuit.
For sensing the position, you can use a loop of wire with a current to voltage converter or a small proximity sensor.
A PID control system with opamps can also be implemented.
Really nice project.
Thanks & Cheers
Congrats! You just made the guts of a speaker!
The information density on your videos is ridiculous. Awesome projects!
Impressive concept put into practice. Thumbs 👍 up. Vast prospects in radionics also.
Solid video, love the quick prototyping of the control problem. We are trying to try to cook up a free piston engine over here as well. MOTŌR smiles upon you, sir. Subbed.
Thanks for the content. It is pretty cool science tool.
Cute little project! I can see that would be something to shoot ball bearings to a good height on a marble course or drawing in and shooting out short streams of water like those 'bouncing water streams' at Disney World I remember seeing.
Dude just made a subwoofer from a tennis ball :) nice work on this video.
"hold your comments" ...moments later " the load " i wasnt even thinking about this till he brought it up 😶
i love the snickering and inuendos, keep those
Excellent work.
this would be a good testbench for inverted pendulum shenanigans. I saw a thing that showed how inverted pendulums on oscillators self-stabilize upright at the right frequency.
Yeah, you know what this is similar too. Brutal. I love it.
Seems like it would be useful for a range of applications
Next level material.
I loved the googly eyed head bobbing so quickly. Good stuff here.
I appreciate the KSP ambiance. ;)
Fascinating! And I didn't snicker once.
I saw a real example of this in a 1950s piece of military tech it was a mechanical oscillator/voltage converter. Self oscillating solenoid with adjustable points and spring, and a coil windingnrectified to produce a high voltage.
It was used as an "inverter" to power high voltage tube radio equipment from a low voltage DC source like 24v.
That's where all the 'good stuff' is. For sure. 40s,50s, early 60s, then things start getting bogged down in over complexity, Fkn 1938. Damn the 80s. 2 steps forward, 3 steps back. Cool World, 1992. That's a banger.
Super interesting
Thanks a lot!
The smile drew me in
memory foam beneath the weight mount would work as dampers say if hammering/jumping effect isn’t desired on ground contact.. the spiral spring is really neat, though a round silicone film would be be more resistant to damage from constant vibrations.. also could add secondary pickup coil as a generator.. wonder if a small oscillator can drive a larger one? inspiring work!
Awesome this is very clever
This channel is so cool. How do you have so little subs haha that will probable change soon !!!
A very interesting project. I was expecting closed-loop control but it turns out to be open-loop. It has finally occurred to me that your voice sounds very much like Jamie Hyneman (Mythbusters).
amazing,,you are so smart
Your way ahead of me so this is to be expected. Good work
Now where are we going hahaha
Pretty cool bro.
Thank you for the share.
I haven't tried annealing, but tempering the bolt (inside the coil) makes it way less permeable to residual flux, which for your case might be quite relevant. I'd also suggest involutes for the spring.
This excellent. Are you going to release a video incorporating a feedback circuit of some kind to keep the resonant frequency in phase ? Thanks
This is really cool! Just be careful because infrasound can be very dangerous. You can make yourself sick if you are too close to an infrasonic pulse, and if it’s amplified, it could even kill you.
4:45 you can say it loud!!!!well done
Great build dude. I have a hypothetical question for you, given some lightweight batteries that can supply enough power to the electromagnets. Do you think hooking three of these up similarly to a wankel style rotary engine could provide enough thrust to lift a small aircraft?
love it, i know what kind of toy i will be building for my wife this Christmas for both of us to enjoy.
Just need a way to replace the smiley face with a container that can hold a small paint jar. You just made a perfect mixer for hobby paints with this contraption.
This gave me ideas…
Very cool
Probably you can get some ideas of building feedback loop from ultrasonic bath schematic. It also tries to keep resonant frequency.
Perfect
Спасибо, вы делаете интересные вещи.
Расскажите пожалуйста, как можно сделать линейный генератор на мембранах с приводом от двигателя Стирлинга.
This is an _excellent_ video, both for the topic / content _AND_ for the process / production values : Thanks !
¶
I wonder what is the Q of this tuned circuit. ¶ If you revised the feedback to be _closed-loop_ and coupled the output to a display (either electrical -or- "analog"/mechanical) the long-term frequency stability would likely be quite good. ¶ It is likely that some "direct synthesis" would be needed to convert the pendulum's frequency (¿up or down?) to some useful frequency. Perhaps several flip-flops with suitable feedback would do it -- if you were lucky -- but it is more likely that synthesis with a PLL (=Phase Locked Loop) would be needed.
§
Over the decades, I have built several closed-loop mechanical pendulums to drive numerous salvaged clock faces, nixie tubes, and Solari® panel. [It had been discarded from a RR station in Tuscanny.] One used an 8" woofer speaker with a laser-pointer reflecting off the cone. Another used an opto-interrupter -- as an "light-beam breaker" -- as a zero-force micro-switch. This was a simple mod to a long deceased "flying pendulum" [=FP] clock. (See Wikipedia if this term is UNclear; YT no longer permits URL's in viewers' comments.) The FP mechanism was likely pre-WWII. The gears, mainspring, face, & hands were useless. I used a 3V motor from a small toy car to provide constant tension for the arm of the FP. This clock had a 1-shaft FP; many clocks use a 2-shaft design. NOTE: There are _many_ YT videos which show an FP mechanism. I used the FP from an existing clock because it was in _good_ condition (including the fragile "pendulum string"!) _&_ because building a working FP was / is far beyond my builder's skills. ¶ I hope others will find all this noise interesting and even useful!
¶
Thanks, again, for this 4⭐ video! ... /Mike - eot - _..._
I'm really interested in whatever feedback mechanism you might come up with.
How could you use a mechanism like this to find resonant frequencies of what it's attached to?
Basically I would like to build something that you could attach to something and find its main resonant peaks and do a Fourier transform of its frequency response..
Like say your goal was to make that table hop and walk...
Add a positive feedback loop that just reads the voltage of the coil and kicks the system at the right moment to sustain the natural oscillations. A small MCU or arduino can do the job.
Seems the inner part of the spring deflects way less than the outer part, modifying the width of the spokes so its thicker on the outer may give you a better performing spring
Nice!
This reminds me of a speaker with many steps
Nice paint rattle cam shaker.
KSP music...top!
Nice project! May I ask what your background is? Do you come from an electrical engineering background?
The lack of si metric standard makes a mess that makes me strugle alot. But beyond that great video i hope u get more and more views
I love these infinite energy generators
Not infinate, Conversion energy
4:26 The sound of my washing Machine 🤣
If you model ridges alone the spring on top of it and optionally the bottom then you can stiffen it too.
Cool!
8:13 kinda cool how the frequency at a point almost looks like a Cool S that we all used to draw
I'm gonna try to make something like that. A function generator along with an amplifier should probably do the trick. Making an efficient electromagnet might be more tricky though
A curiosity.
Some thoughts come to mind. Would the barbell steel still be as "jumpy" with a system designed at a higher resonant frequency? Is it possible that your oscillator is merely near a harmonic of the steel against the floor?
Maybe it would be possible to alter the tension of the spring so that on the upstroke it's travel is limited, but on the downstroke it has more range. Perhaps by simply adding a plate above the spring to prevent it's motion. As I see it, the barbell is absorbing the energy of the spring, but at 180 degrees, and with much less motion due to it's larger mass. But if the spring transferred more force on the upstroke than the downstroke, wouldn't it stand to reason that an object's weight could be reduced?
First of all a harmonic only concerns acoustic sound, secondly, you would need a very high frequency to reach atomic resonance. Water is 2.4 Ghz
The barbell weight is probably cast iron instead of steel. If you used any liquid (oil, cutting fluid, WD40, etc) it would almost instantly dull the drill. Cast iron has tiny grains of iron carbide in it which mix with the liquid forming a slurry similar to lapping paste. Drill cast dry. Cool with compressed air.
I did not know that. Thanks!
The stack of springs also limits sideways rotation of the 'pendulum.'
Is it worth the added complexity to balance two oscillators, one electromagnet and a sprung magnet on each end?
As a long time electronics tech, I do a lot of electronics experiments and I've often wondered what the power companies snoopers thinks while viewing their electrical smart meter data. I'm sure that some of them are scratching their heads at some of our usage.
This seems fun. As a side note has anyone 3ver said you sound a lot like prozd?
I honestly don't know what jokes people could say about it.
Oh My, that ball looks unusually happy.
Did you use hall effect sensors to measure oscillation of the mechanical system through the oscilloscope or did you just measure induced I/V
It looks like you made a bass speaker that resonates around 5-15 Hz, kick up that oscillator to about 40 to 60 hertz, and you got yourself a bass speaker. You know, when I was a kid, I was infatuated with speakers, and their design, and, in 6th grade, invented a bass speaker with a push-pull, dual coil design. Think of two speakers bolted together, one has reverse polarity of the other. That's right, I invented a dual voice coil speaker in 1986, when I was 11 years old! I still have the piece of lined paper I pulled out of the notebook that I scribbled this on, during my history class. That speaker is now used in very high-end systems, and can go for upwards of $1,000 Plus. I also got a 99 in my science class or my invention. I played with RC cars as a child. It was no surprise I came up with the first remote control lawn mower, which happened to blow away my science teacher. he was amazed. Someone profited from that one as well, because there are many on the market now, and are also very expensive, as well.
Did you reinvent the post it note too? 🤪
You can let the 555 adjust to a sensor of the current jump frequency.
Could do the feedback using a piezo underneath the whole assembly.
Can you make a quartz clock, but with this instead of a quartz Crystal?
That's all a bass speaker is. The cone is designed to hold the cylinder in midair, where it floats, and can deflect up and down, over a magnet. Then you just put an oscillating frequency (sine wave) pwr. into the coil, the coil reacts against the magnet, and, up and down you go. It's magic, 120 year old tech.
To be able to hear the bass with our human ears, you need a minimum of 40 to 60 hertz. The human hearing scale is from 40 to 60 hertz, up to upwards of 20 kilohertz. 40 to 60 HZ will just give you a headache, 20 plus kilohertz can damage your ears, when the decibel level is very high.
Awesome! Can it be made into a 60 Hz generator?
If you add a model of the new Shepard instead of the ball you have a super nice looking lauch simulator
Could you add high voltage ceramic capacitors instead of a weight on the spring ant then run it the charge discharge cycle at 4 harmonic to test out machs principle???
Cool! Now take the upper portion and apply friction that shows it become damped/overdamped/critically damped for all the engineering nerds
Can you also make galvo ?
The width of the coil should vary either in its thickness or in tapered coil to center. You have rhythmic vibrations your dealing with young Sir.
Congratulations, you built a subwoofer
Muy buen oxilador,ingenio puro,más conocimiento,,.😃👍🇺🇾
And here I was thinking I'm the only person who reads NASA cryocooler literature for personal enrichment!
Like # 201.... Interesting stuff there. Thanks.
You should also make the circuit resonant at the same frequency
Why does a ball with eyes moving up and down make me laugh so hard??)))
It's that big grin smile
💖
I rebuild Sumitomo ColdHeads (Cryo coolers) that maintain 0% boil off of LHe in MRI magnets. Our "RDK" Coldheads have two stages inwhich the 2nd stage goes down to 4 Kelvin under load in order to recondence helium vapor that naturally wants to boil off back into a liquid.
The Sterling effect that achieves these temperatures is generated by a compressor that brings the He to close to 200 PSI while a motor whose high to low pressure value is guided by a grease filled shielded Z bearing.
The only springs you'll find in that entire system is to space the supply line
Also, it's ENTIRELY possible I misunderstood, but it sounds like you're under the impression that a Cryocooler is the compressor? But instead, the Cryocoolers requires an external compressor to compress the He gas in order for the Sterling Effect to move the displacer and extract heat through a system that is analogically closer to a Thermal Acoustic System (See "Nighthawk's video on Sound Refrigeration).
The systems I'm talking about are usually small self-contained stirling cycle coolers that get attached to some sort of sensor like an IR camera that needs to be cooled to ~70K or so.
I'm guessing the cold heads you're working with are the "Gifford-McMahon" type that are basically a modified stirling cycle where the cold head goes in a dewar and it's connected to a separate compressor unit by some flexible lines?
PS, if you happen to know where i can get some reasonably priced spares/surplus of the kind of equipment you work with, send me an email, cause i've been trying to build a cryocooler forever
always wondered why they made that noise
Turn this into one of the thumper machines in old Dune movie.
my homeowner's insurance doesn't cover sandworm damage
Is that a specified exclusion clause or just an assumption?